Digital signal processing is used in a wide variety of applications. Many of these applications are real-time in the sense that time constraints exist on the processing of the data in order for it to be meaningful or useful to an end user. An example of this is digital broadcast streams, such as digital television and digital radio. The digital signal processing system needs to be capable of processing and decoding the real-time streams rapidly enough to enable the data to be output as quickly as it is received (barring buffering).
Digital signal processing systems may utilise a plurality of different types of processing elements. For example, such a system can comprise digital signal processors (DSPs), general purpose processors, and specialised hardware peripherals designed to perform a specific signal processing task. Each of these different types of processing elements may utilise one or more memory devices for storing data and/or software code.
For demanding applications, such as real-time data, speed of memory access is a critical factor in the performance of the overall digital signal processing system. To enable fast memory access, the memory devices can be tailored to operate efficiently with the type of data being processed. For example, a particular processing element can be connected to a dedicated memory device that enables fast memory access for that element for a specific type or structure of data.
However, the use of dedicated and specialised memory devices limits the ability of the digital signal processing system to be flexible and configurable to different types of real-time data. For example, the various different digital television and radio standards used around the world often have the real-time data structured differently. It is therefore difficult to provide a digital signal processing system that provides fast memory access for each of these different types of data, without constructing a different digital signal processing system for each data type.
The embodiments described below are not limited to implementations which solve any or all of the disadvantages of known digital signal processing systems.